Sawmill



July 1, 1924. 1,499,756

- L. H. STREET SAWMIbL Filed March 18, 1 22 4 Sheets-Sheet 1 Ehwe/mtoz srwmm July I 1924.

L. H STREET S AWM I LL Filed March 18, 1922 4 Sheets-Sheet 2 avwanboz fem mm July 1, 1924. 1 1,499,756

.. L. H. STREET 4 SAWMILL {filed March 18, 1922 4 Sheets-Sheet.

avwa nto'z @331 um/W July 1 192 l.499,756 L. H. STREET SAWMILL Filed March 18, 1922 4 Sh ets-Sh t, 4

m i. 5mm

50 for, reversing the movement of the. carriage.

Patented July 1, 1924.

TET o Fw LOUIS nsrannr, or OLEAN, nnwyonx.

SAWMILL.

Applioation filed March 18, 1922.

new and useful Improvement in Sawmills,

of which improvement the following is a specification.

';Tl 1is invention relates in general to saw mills for cutting logs into lumber of various ,kindsand sizes," but is more particularly ment quickly,

adapted for use in sawing short logs or bolts, asthey are termed, where the saw mill carriagehas a short travel, and itis important 'to reverse the direction of mov eln this class of work, the short logs, w h may be from 2 feet toabout- 4 feet long, and from 8 inches to 24 or more inches in diameter, are sawed into square sticks, varying from g of an inch to 1 inches square, to be used as turning stock by woodworking plants. Circular saws have been used for this work but on account of the heavy kerf made by acircular saw, resulting in a considerable loss of stock in sawdust, I prefer to use a band saw: which makes only a narrowkerf; and thereby effects-a saving in stock. However, while some offthefeatures of my invention are particularly adapted for bandsaw mills, other features are of broad application and, are equally well adapted for use ,with. circular Saws. 7

One of the objects of -n1y invention is to speed .upthe operation effecting a'quicker reversing action and return move-mentof the carriage,..and for this purpose I providea return spring or, other elastic-means, adapted to ;be; engaged and thrown into ,action upon the carriage duringthe last part of its forwardor {cutting movement, and .just prior to the instant of reversing the driving mechanism, whereby the momentum, of the carriage .will be stopped, and its :return movement begun-without waiting for the re turn frictiondrive to effect thisfaction. The return friction will then start-very quickly,

I 7 thereby. avoiding delay and wear upon the friction mechanism. 7 v Y Another feature of my invent1on comprises an .improved automatic trip ,dev ce ,Afurther' object is to .providean improved driving connection from the rope drumto thecarriage,--when used in connection with a hand saw mill, in which the rope .drum shaft remains parallelwith. the main band wheel S erlal No.- 544,717.

shaft and the direction of inovementof the carriage.

Still another object isto provide means for guiding the bolt or dog when used wit-ha band saw, whereby the bandis relieved from excessive pressure and thebolt is required to travel true and parallel'with the band. Still another feature comprises an improved earriageconstruction with-adjustable dog blocks adaptedtosbe quickly and easily brought to any desired position.

"In the accompanying drawings Figure 1 is a side elevation of a saw mill carriage and operating mechanism embodying my improve1nent,,as applied to a" bandsaw; 'FigfiQ, aplan ofsame; -Fig. 3, a "detail view,;in section, of the return spring and'cylinder; Fig. 1, anend elevation of the milland carriage with certain partsshown-in-section;

and, Figs5 and -6, an end elevation and plan, respectively, showing the'friction drive and trip mechanism for reversing the same.

In the practice .of my invention, any suitable form of carriage maybe employed,'but I have shown acarriage composed of two channels, '8, mounted on the castings, '9,

forming a supporting frame and having bearings for the truck wheels,10,which riin on a track, 111, the. wheels at; one side being groovedto engage a V track rail in the usual manner. The wire rope, 12, fordriving. the carriage is connected atitsends to the car'- riage lby suitable eyebolts, and passes over thefixed idle wheels,1 3,13 at opposite ends.

of the track and'then over theidlewhels, 14}, 14g, and aroundthe rope drum, 15, which is fixed'on the sl1aft, 16,of thedrivingfriction wheel, 17. The j friction wheel, 17,; is formed with an annular flange or rim adapted in one position to; have external engagement withjfixedfriction wheel, 18, and in another.

position to 1 have internal engagement with friction wheel; or pulley, 119," the bearing of shaft, 16, Q211IY1I1gf the' drivin'g friction, 17, being, mounted in the rocker box or arm, 2( and actuated, from one position to the other by link, 21, and crank, 22, on the pedal shaft, 23. 'i 'lhe friction wheels; 18' and =19, are mounted on the respective shafts, 24: and 25, and are driven by suitable pulley',. and" belt connections in the usual way. ,The pedal,-26, is carried at the outer endsof the pedalgarms 27, whichareffixed upon; the shaft, 23, and

normally held by a springy28, in suchposi t-ion tha th dr v ngfl c n. he 11. gages the returnor recedefrictron wheel," 18,

which drives the rope drum 15, in the di rection to propel the carriage upon its backward or return stroke. When the pedal is pressed down, the driving friction wheel, 17 is swung over into engagement with the forward or feed friction wheel, 19, which operates to propel the carriage on its forward or cutting stroke.

7 In the operation of sawing up the bolts, or short logs, it is the practice for the operator to adjust and hold the bolt by hand and not to clamp the bolt to the carriage for the forward cutting stroke, except for the first out when the slab is removed, at which time the log may be clamped, or dogged, as it is termed, by suitable dogs mounted on the carriage. I have shown one form'of dogs for this purpose, comprising castings, 30, having T-headed bolts, 31, extending through the slot between the channels, 8, of the carriage, which slots run substantially the full length of the center of the carriage and provide an adjustable locking way for the bolts, 31,,Whereby the dog castings, 30, may readily be adjusted and locked in any desired position by turning the handle of the locking nuts, 32. On the dog castings are mounted the movable dog points, 33, operated by hand lever, 34, and adapted to be set into the end of the log to securely hold the same to the carriage.

For the purpose of guiding the bolt in its forward movement, and for gauging the thickness or width of the cuts, I have shown the adjustable guide, 35, which may be a steel angle, mounted on the table, 36. The position of the guide may be quickly adj ust ed by means of the attaching links, 37, and lock handle, 38, todetermine the thickness of the stock.

In accordance with one of the features of my invention, I provide automatic mecha nism for reversing the direction of movement of the carriage at the end of its forward travel and elastic means adapted to be engaged by the carriage in advance of the action of the reversing mechanism, for overcoming the inertia of the carriage, and starting the same on its return movement. One form of tripping mechanism for shifting the reversing mechanism of the carriage is shown as comprising a slidably mounted rod, 40, having a spring, 41, for pressing said rod outward against a. trip pin, 42, at its end, and a tappet collar, 43, adapted to be engaged by the projecting arm, 44, fixed upon the carriage, 8, for tripping said pin at the end of the forward stroke of the carriage. The pin, 42, slides through a guide plate, 45, and through an opening in the pedal, 26, being provided with a nut under the pedal and a spring, 46, between the pedal and a collar, 47, on. said pin.; As one form of elastic means for arresting and reversing the movement of the carriage, I have shown a fixed cylinder or casing, 48, containing an adjustable spring, 49, plunger, 50, and stem, 51, adapted to engage a buifer block, 52, of wood vor other suitable material, mounted at the end of the carriage, the dimensions being such that the stem, 51, is engaged by the buffer block, 52, in advance of the engagement of the arm, 44, with the collar of the trip rod, 40.

When the carriage nears the ends of its forward travel, the block, 52, strikes the stem, 51, comprising the spring 49, which then exerts sui'licient force to arrest the carriage and start it on its return movement just as the arm, 44, strikes the collar, 43, of the rod, 40, and releases the trip pin, 42. The spring 28, thereupon pulls up the pedal arm, 2 to shift the driving friction wheel, 17, into engagement with the reverse or recede friction, 18, as shown in Fig. 5, thereby reversing the rope drum, 15, to return the carriage. The action of the spring, 49, in thus arresting the carriage and starting the same on its return stroke greatly relieves the stress and wear upon the reversing friction so that the same will start easily and quickly and drive the carriage through its return stroke. When the carriage reaches the end of the return travel it strikes the plunger stem, 53, of the buffer spring, 54, contained in fixed casing, 59, which acts as a stop to slip the friction, and is held there while the operator turns or adjusts the bolt to the desired position for the next out, after which he steps upon the pedal forcing it downward against the spring, 28, until the trip pin, 42, is below the end of the shaft, 40. The spring, 41, then forces the shaft, 40, over the top of the pin, 42, and locks the pedal in position by means of the spring, 46. By the movement of the pedal to this position, the driving friction wheel, 17, is thrown over into engagement with the forward or feed friction wheel, 19, as indicated in Fig. 6, which operates to drive the rope drum forward and propel the carriage forward through its cutting stroke.

Where my invention is employed in connection with a circular saw mill, the shafts of the friction pulleys will preferably be parallel with th shaft of the saw and driven by a simple belt connection, in which case the axis of the rope drum is at right angles to the direction of movement of the carriage. I prefer, however, to use a band saw mill, and have indicated the same in the drawings by the band saw, ,55, passing over the upper and lower band wheels, 56 and 57. In

this case, the power shaft, 58, for driving the lower bandwheel and the saw is parallel with the saw and the direction of movement of the carriage, and the shafts of the friction wheels are also parallel therewith V in order to use ordinary belt connections. This arrangement, however, makes the axis of the rope drum parallel with the direction of movement of the carriage and in order to operate the rope from the drum in this position, I have introducedintermediate guide means for deflecting the rope, such means being shown as the two idle rope wheels, 14 and 14*, above the drum, 15, and between it and the respective idle wheels, 13 and 13,

at the oposite ends of the track. By this 7 means the rope may pass from the drum directly over the idle' wheels to the car riage, and the use of'bevel gears or other means for driving the drum at right angles is avoided.

Another feature of my invention when used with band saw mills, is the adjustable guide plate or pressure plate, 60, which is sup-ported on a bracket, 61, just at the rear edge of the band saw, 55, and is provided with suitable adjusting screws at the top and bottom. This plate is for the purpose of affording a stiff surface for the operator to hold the bolt against in making the cut. The dog points are used only during the first cut or when trimming the log, while in the rest of the operation of sawing up the stock the bolt is not locked at all but is merely pushed against the guide plate and held there by the operator while each cut is beingmade. The band saw itself does not offer sufficient surface fore/the operator .to bear against. The position of the guide plate may be readily adjusted by means of the adjusting means so as to be kept in perfect alignment with the band saw.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a saw mill, the combination with a carriage, and a friction mechanism for driving the carriage in opposite directions, of a pedal device for reversing the friction driving mechanism, a tripping mechanism for holding the pedal depressed, and a tappet device o perated by the movement of the carriage at the end of its forward stroke for releasing the trippingmeohanism.

2. In a saw mill, the combination with a carriage, and a friction mechanism for driving the carriage in opposite directions,

of a pedal device for reversing the friction driving mechanism, a trip pin connected to the pedal, a tappet rod for holding down the trip pin, and an arm carried by the carriage for releasing the tappet rod from said trip pin.

In testimony whereof I have hereunto set my hand.

' LOUIS H. STREET. 

